NEW ORLEANS -- Take ’Em Down Nola, the group that urged Mayor Mitch Landrieu to remove the four Confederate monuments, on Friday suggested a private security contractor the administration hired might have hacked members’ email inboxes and social media accounts and infiltrated their ranks.

That led City Hall to say for the first time that no local groups were under surveillance, while a defiant Landrieu defended the security measures that were taken.

“They can criticize me all they want,” he told Eyewitness News after speaking about the monument removals at the Center for American Progress in Washington, D.C. “There were real and there were imminent threats. What would they have thought if somebody would have actually gotten shot or hurt?”

Malcolm Suber with Take ’Em Down Nola and a vocal opponent of the monuments said during a Friday morning press conference on the steps of City Hall that he couldn't say for certain that anyone infiltrated his group but had filed a public-records request trying to find out if that happened.

He said he became suspicious after it appeared the group’s social media pages were “tampered with” and his computer hacked in some way.

City Hall spokesman Tyronne Walker later said that Suber’s group was not spied on. “No local group was tagged for surveillance.”

The city has said “racial extremists” forced the administration spend $710,000 to contract with Trident Response Group, a Dallas-based private security firm that provided “threat assessments.”

The city announced last Friday it cost $2.1 million to remove the monuments. The city covered roughly half that cost, with the difference coming from private donations.

Among other things, Trident infiltrated groups on both sides of the monument-removal debate, The New Orleans Advocate reported.

When announcing the expense, City Hall did not provide details about which groups were spied on, but they did confirm Trident personnel were on the ground in an undercover capacity during protests. Walker would not say Friday which groups were looked at.

Suber said City Hall’s denial that Take ’Em Down was looked into wasn’t enough to satisfy his concerns.

“The statement we are working off is they were investigating both sides,” Suber said. “For them to claim they were not spying on us it not credible to us.”

Meanwhile, a City Hall source questioned Take ’Em Down’s motives since extra police protection was offered to Suber and his group when they marched to protest at Jackson Square and Lee Circle at separate times, with Superintendent Michael Harrison speaking personally to Suber each time

Suber during a later phone interview acknowledged the extra protection the city provided.

“We just think the mayor ought to answer some questions,” he added. “How can you justify spending $1.1 million?”

Earlier in the morning, Landrieu said he had no regrets about the cost for the extra security efforts.

“Not only do I not apologize for that … I think the shooting of Congressman Scalise just highlights the fact of how necessary it is and how right we were to be very, very careful so that nobody got hurt,” he said.